The first tweener done in official competition: Vilas!

The shot was executed for the first time in 1974 at the courts of the Club Obras Sanitarias of Buenos Aires in an exhibition match against the French player Wanaro N'Godrella. In a official match, the shot was executed by Vilas for the first time in 1975 in the Indianapolis tournament on clay, against the Spanish Manuel Orantes. I don´t remember if I heard some time that he made it in a previous game, but anyway, it's true; and you can see a text of his book "Quién soy y como juego"(1976) in which he describes how he discovered that shot:

No kidding! You must be precise! I had forgotten that we used to call this shot "the hot dog". I was researching to see if it is understood that Vilas was the first and came across this yahoo answer that does not answer but has some insights.

Great picture. It is universally agreed that Vilas invented the tweener? So, what is the documentation? Just Vilas saying he did it first in a real match? I mean, I believe him but there must be others that claim to be the first. I imagine there are many that would do it in practice or even practice matches, and there would be many claims of first. So I think the real test is first sanctioned match.

My tennis years, the mid '70's, Nastase's backfire was the "in" shot. We knew about the tweener and the reverse bolo, but Nastase's shot was often a clean winner against top 30 PRO mens. So everyone tried it a few times, very few every figuring it out. Nastase could hit it DTL or short angle CC, even from the ad side of the court. A true goofaround genius, that twisted dude.